Extreme Board is designed as a fucking machine for sitting positions.
The board has a soft pillow and drive with levers mechanism.
Person is sitting on a pillow. Levers mechanism provides stroking motions of dildo. Dildo position is adjusted on an
optimal height over the pillow for sitting position, and may be sub-adjusted up-down for personal features.
The stroke may be adjusted by moving the crankshaft joint on the lever from 3" - 5" (7 to 12 cm).
Frequency is regulated by remote control.
Machine is very convenient for long term sexual acts. It may be installed on a bed or sofa with back pillows, providing comfortable body position.
Principle of action
(In this demonstration clip, dildo is fixed to the lever.
But in "real life" dildo is swinging free on its axle, and moves horizontally.)